Vol. 6
September Issue
Year 2005


in Vol. 6 - September Issue - Year 2005
PEP Technology For Optimal Shot-Blasting Equipment Effects For Purge Of Castings Of Ferrous And Aluminium Alloys

PEP wheel

Standard shot-blasting machine with hanging hook

Custom-made shot-blasting machine for the process for destroying radioactive elements

 In the Spotlight

Gostol-T.S.T. d.o.o. Slovenia – Company Profile GOSTOL - T.S.T. d.o.o. TOLMIN is an internationally recognized company with a long manufacturing tradition. The company production programme takes in shot blasting equipment, foundry equipment, welding construction, design engineering and technical consultancy, and after-sales servicing. The company employs around 100 people. With more than 50 years of technical experience and more than 800 buyers in more than 30 countries Gostol-TST is recognized for its high-quality products.

Key Words: Shot blasting, PEP blasting technology, blast turbine, custom-made shot-blasting machines, costs, savings.

PEP technology in shot blasting

By means of great investment in research and development in recent years Gostol-TST has developed a throwing wheel with curved blades known as PEP, and an automatic ADV PEO abrasive dosage valve, both connected with what has become known as PEP technology. The ADV automatic abrasive dosage valve is used for dosing abrasive means into the throwing wheel. It enables automatic abrasive flow regulation dependent on the desired turbine power and automatic adaptation of abrasive flow depending on the turbine rotating velocity. It removes the possibility of reduced efficiency and overloading and reduces the influence of the human factor on blasting capacity and quality.

With a combination of different types of material it is possible to achieve very different characteristics of blasting, blasting times and cost. PEP technology offers:

-reduced costs of blasting-cleaning
-increased productivity due to shorter blasting time
-increased wearing parts of turbine wearing parts (reduced maintenance costs and breakdowns)
-blasting process controlled ‘on line’
-precise blasting direction of the abrasive jet
-archive abrasive jet power regulation with PEP ADV automatic dosage valve

PEP technology has been developed for reducing blast cleaning costs, meaning approx. 20 % lower energy costs, approx. 10 % lower abrasion costs, and approx. 20 % lower maintenance costs.
The PEP throwing wheel is used for abrasive acceleration, and reaches an outlet speed up to 30 % higher than a classic wheel. The blasting time is shorter by between 20 – 30 %. Two types of rotor with curved blades are installed depending on the working conditions, with carbide blades for heavy-duty conditions such as in a foundry or cast blades. The life span of carbide blades is at least 20 times longer than that of cast blades.

Standard machines for automated blasting

PEP technology is suitable both for new machines and for the adaptation of old machines.
When choosing standard machines it is necessary to consider:

-high-capacity requirements for shot-blasting
-mid-quality requirements of shot-blasting
-mid requirements for iterate processing
-labour costs and energy costs have a crucial impact

In the case of small-batch production an optimal purchase would be a universal machine for automated blasting. These machines are assembled from a parcel or continual universal transportation system that transports the products through the blasting module by universally provided blasting wheels. A high capacity of blasting is achieved by these machines, as well as an appropriate quality of the blasting surface. Different types of products can be processed thanks to the universality of these machines. A high purchase price and relatively low labour costs are characteristic features of the given machines.
High capacities are achieved with mass blasting of work-pieces in large blasting machines. Under mass blasting the complete surface of a separate work-piece is not blasted under the same angle and with the same intensity.
As regards energy these machines are very suitable. Additional savings may be achieved by the installation of modern and highly efficient turbines that besides additional savings of energy also provide savings of abrasive.

Custom-made machines for automatic blasting

Typical requirements for the selection of blasting equipment are as follows:

-mid-capacity requirements for blasting
-high-quality requirements of the blasted surface
-high requirements for iterate processing
-labour costs and energy costs have a crucial impact.

The purchase of a custom-made machine for automatic blasting is optimal in the case of large-batch production or special production or cleaning environment, for example the nuclear industry as seen from the pictures. The transportation system is adjusted to the work-piece and accelerators are ranged in the blast module so as to enable the optimal coverage of the complete surface of the item related to the angle of incidence of the abrasive blast, as well as the intensity of blasting per unit of surface. All these ensure high blasting quality. These machines may also have a fast phase of operation, besides high iteration, mainly under smaller work-pieces and where transportation and handling are not difficult. A purchase price that is relatively high and low labour costs are characteristic of these machines.

Author: Ivan Markocic and Ales Jurman, BSc. in mechanical engineering

Tel: +386.5.380 1280, Fax: +386.5.380 1290
E-mail: info@gostol-tst.si, www.gostol-tst.com